Main Page | See live article | Alphabetical index Incubation period is the time elapsed between exposure to a disease organism and when symptoms and signs are apparent. The period may be as short as hours to as long as thirty years in the case of variant Creutzfeldt-Jakob disease (mad cow disease). A person may be a carrier of a disease, such as strep throat, but not have any symptoms. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.